April 8 2024

Carl, Cedric, Damien, Daniel, Evan, Jan, Junchao, Gabriel, Matthew, Marc, Nicole, Stephen

Note-taker

Carl, Jan, Stephen, Gabriel, Evan, Hugo, Joseph, Vivek

General Topics

• Friction points or adjustments to be made to repository management?
  • All is well
• Drop mdspan support for now?
  • Quite natural to extend Kokkos::View to mdspan once it's more fully baked
  • Yes - don't worry about supporting this with anything new you write, but we won't take anything out
  • Jan: we have a summer intern coming in who will look at mdspan to see how to handle concerns about data placement, etc (e.g. through accessor interface, maybe inspired by raft?)
• Kokkos org migration: Carl will work with Damien Lebrun-Grandie to make this happen
  • The group can nominate one (or two?) folks to be elevated to maintainer
• Please contact Carl ([email protected], slack) with your github ID if you want to be marked as a collaborator on the repo.
• Do Sandia folks want to reserve a room? (physical attendance not required)
  • Carl will do this
• A logo???
  • Jan has some ideas for Kokkos sub-project logos
  • Damien: there will be some Kokkos trademark rules/restrictions we will need to be careful of, check with Trott
• Junchao:
  • MPI types are in the parameters, so should MPI be in the name?
    • Carl: people today use Kokkos + MPI, so we know that's somewhere we can be useful. We chose KokkosComm to reflect some broader ambition of the project even though the initial implementation is basically an MPI wrapper. Going to put MPI wrappers in Impl for now since we will need them eventually, but not wedded to a specific public interface yet.
• Cedric:
  • Forum for longer-form async technical discussion?
  • Carl will enable discussions on Github and we can try it

Working Groups

• Application Usecases
  • Carl working on thin MPI wrappers in Impl namespace
• Modern C++ / MPI
  • Jan and Gabriel are starting to think about this.
• Accelerator-Initiated Communication / Support
  • Evan & Tony's group interested in this, also NCCL, no updates
  • Junchao: nvshmem and other shmems rather than NCCL for accelerator-initiated communication?
  • Cedric: CEA more interested in two-sided here. relationship with remote spaces?
    • Jan: RS is high level distributed view. Kokkos Comm may be able to provide a useful lower-level API
• Smart NICs
  • coordinating a smart-NIC for HPC talk by Richard Graham in 2-3 weeks, may be a place where we can have an impact

Roundtable

• Carl

  • make install working (and CI test) #14
  • Don't need -DCMAKE_CXX_COMPILER=mpicxx #19

• Cedric

  • Helping review & inform software engineering stuff. This is the time to make a good foundation.

• Evan

  • no updates

• Gabriel

  • thinking about senders / recvrs + MPI and/or PIKA and/or HPX with Jan

• Jan

  • Monthly meeting with PIKA folks, talking about improved programming models. Will invite Gabriel (and anyone else)

• Marc

  • no updates

• Matthew

  • no updates

• Nicole

  • Will be at Sandia this summer

• Stephen

  • no updates